loader/task.c

   1 /*
   2  * Task functions
   3  *
   4  * Copyright 1995 Alexandre Julliard
   5  */
   6
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <assert.h>
  10 #include <unistd.h>
  11
  12 #include "wine/winbase16.h"
  13 #include "callback.h"
  14 #include "drive.h"
  15 #include "file.h"
  16 #include "global.h"
  17 #include "instance.h"
  18 #include "miscemu.h"
  19 #include "module.h"
  20 #include "neexe.h"
  21 #include "process.h"
  22 #include "queue.h"
  23 #include "selectors.h"
  24 #include "stackframe.h"
  25 #include "task.h"
  26 #include "thread.h"
  27 #include "toolhelp.h"
  28 #include "winnt.h"
  29 #include "winsock.h"
  30 #include "syslevel.h"
  31 #include "debugtools.h"
  32 #include "dosexe.h"
  33 #include "services.h"
  34 #include "server.h"
  35
  36 DEFAULT_DEBUG_CHANNEL(task)
  37 DECLARE_DEBUG_CHANNEL(relay)
  38 DECLARE_DEBUG_CHANNEL(toolhelp)
  39
  40   /* Min. number of thunks allocated when creating a new segment */
  41 #define MIN_THUNKS  32
  42
  43
  44 static THHOOK DefaultThhook = { 0 };
  45 THHOOK *pThhook = &DefaultThhook;
  46
  47 #define hCurrentTask (pThhook->CurTDB)
  48 #define hFirstTask   (pThhook->HeadTDB)
  49 #define hLockedTask  (pThhook->LockTDB)
  50
  51 static UINT16 nTaskCount = 0;
  52
  53 static HTASK initial_task;
  54
  55 /***********************************************************************
  56  *           TASK_InstallTHHook
  57  */
  58 void TASK_InstallTHHook( THHOOK *pNewThhook )
  59 {
  60      THHOOK *pOldThhook = pThhook;
  61
  62      pThhook = pNewThhook? pNewThhook : &DefaultThhook;
  63
  64      *pThhook = *pOldThhook;
  65 }
  66
  67 /***********************************************************************
  68  *           TASK_GetNextTask
  69  */
  70 HTASK16 TASK_GetNextTask( HTASK16 hTask )
  71 {
  72     TDB* pTask = (TDB*)GlobalLock16(hTask);
  73
  74     if (pTask->hNext) return pTask->hNext;
  75     return (hFirstTask != hTask) ? hFirstTask : 0;
  76 }
  77
  78 /***********************************************************************
  79  *           TASK_LinkTask
  80  */
  81 static void TASK_LinkTask( HTASK16 hTask )
  82 {
  83     HTASK16 *prevTask;
  84     TDB *pTask;
  85
  86     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
  87     prevTask = &hFirstTask;
  88     while (*prevTask)
  89     {
  90         TDB *prevTaskPtr = (TDB *)GlobalLock16( *prevTask );
  91         if (prevTaskPtr->priority >= pTask->priority) break;
  92         prevTask = &prevTaskPtr->hNext;
  93     }
  94     pTask->hNext = *prevTask;
  95     *prevTask = hTask;
  96     nTaskCount++;
  97 }
  98
  99
 100 /***********************************************************************
 101  *           TASK_UnlinkTask
 102  */
 103 static void TASK_UnlinkTask( HTASK16 hTask )
 104 {
 105     HTASK16 *prevTask;
 106     TDB *pTask;
 107
 108     prevTask = &hFirstTask;
 109     while (*prevTask && (*prevTask != hTask))
 110     {
 111         pTask = (TDB *)GlobalLock16( *prevTask );
 112         prevTask = &pTask->hNext;
 113     }
 114     if (*prevTask)
 115     {
 116         pTask = (TDB *)GlobalLock16( *prevTask );
 117         *prevTask = pTask->hNext;
 118         pTask->hNext = 0;
 119         nTaskCount--;
 120     }
 121 }
 122
 123
 124 /***********************************************************************
 125  *           TASK_CreateThunks
 126  *
 127  * Create a thunk free-list in segment 'handle', starting from offset 'offset'
 128  * and containing 'count' entries.
 129  */
 130 static void TASK_CreateThunks( HGLOBAL16 handle, WORD offset, WORD count )
 131 {
 132     int i;
 133     WORD free;
 134     THUNKS *pThunk;
 135
 136     pThunk = (THUNKS *)((BYTE *)GlobalLock16( handle ) + offset);
 137     pThunk->next = 0;
 138     pThunk->magic = THUNK_MAGIC;
 139     pThunk->free = (int)&pThunk->thunks - (int)pThunk;
 140     free = pThunk->free;
 141     for (i = 0; i < count-1; i++)
 142     {
 143         free += 8;  /* Offset of next thunk */
 144         pThunk->thunks[4*i] = free;
 145     }
 146     pThunk->thunks[4*i] = 0;  /* Last thunk */
 147 }
 148
 149
 150 /***********************************************************************
 151  *           TASK_AllocThunk
 152  *
 153  * Allocate a thunk for MakeProcInstance().
 154  */
 155 static SEGPTR TASK_AllocThunk( HTASK16 hTask )
 156 {
 157     TDB *pTask;
 158     THUNKS *pThunk;
 159     WORD sel, base;
 160
 161     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
 162     sel = pTask->hCSAlias;
 163     pThunk = &pTask->thunks;
 164     base = (int)pThunk - (int)pTask;
 165     while (!pThunk->free)
 166     {
 167         sel = pThunk->next;
 168         if (!sel)  /* Allocate a new segment */
 169         {
 170             sel = GLOBAL_Alloc( GMEM_FIXED, sizeof(THUNKS) + (MIN_THUNKS-1)*8,
 171                                 pTask->hPDB, TRUE, FALSE, FALSE );
 172             if (!sel) return (SEGPTR)0;
 173             TASK_CreateThunks( sel, 0, MIN_THUNKS );
 174             pThunk->next = sel;
 175         }
 176         pThunk = (THUNKS *)GlobalLock16( sel );
 177         base = 0;
 178     }
 179     base += pThunk->free;
 180     pThunk->free = *(WORD *)((BYTE *)pThunk + pThunk->free);
 181     return PTR_SEG_OFF_TO_SEGPTR( sel, base );
 182 }
 183
 184
 185 /***********************************************************************
 186  *           TASK_FreeThunk
 187  *
 188  * Free a MakeProcInstance() thunk.
 189  */
 190 static BOOL TASK_FreeThunk( HTASK16 hTask, SEGPTR thunk )
 191 {
 192     TDB *pTask;
 193     THUNKS *pThunk;
 194     WORD sel, base;
 195
 196     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
 197     sel = pTask->hCSAlias;
 198     pThunk = &pTask->thunks;
 199     base = (int)pThunk - (int)pTask;
 200     while (sel && (sel != HIWORD(thunk)))
 201     {
 202         sel = pThunk->next;
 203         pThunk = (THUNKS *)GlobalLock16( sel );
 204         base = 0;
 205     }
 206     if (!sel) return FALSE;
 207     *(WORD *)((BYTE *)pThunk + LOWORD(thunk) - base) = pThunk->free;
 208     pThunk->free = LOWORD(thunk) - base;
 209     return TRUE;
 210 }
 211
 212
 213 /***********************************************************************
 214  *           TASK_Create
 215  *
 216  * NOTE: This routine might be called by a Win32 thread. Thus, we need
 217  *       to be careful to protect global data structures. We do this
 218  *       by entering the Win16Lock while linking the task into the
 219  *       global task list.
 220  */
 221 BOOL TASK_Create( NE_MODULE *pModule, UINT16 cmdShow, TEB *teb, LPCSTR cmdline, BYTE len )
 222 {
 223     HTASK16 hTask;
 224     TDB *pTask;
 225     char name[10];
 226
 227       /* Allocate the task structure */
 228
 229     hTask = GLOBAL_Alloc( GMEM_FIXED | GMEM_ZEROINIT, sizeof(TDB),
 230                           pModule->self, FALSE, FALSE, FALSE );
 231     if (!hTask) return FALSE;
 232     pTask = (TDB *)GlobalLock16( hTask );
 233
 234     /* Fill the task structure */
 235
 236     pTask->hSelf = hTask;
 237
 238     if (teb->tibflags & TEBF_WIN32)
 239     {
 240         pTask->flags        |= TDBF_WIN32;
 241         pTask->hInstance     = pModule->self;
 242         pTask->hPrevInstance = 0;
 243         /* NOTE: for 16-bit tasks, the instance handles are updated later on
 244            in NE_InitProcess */
 245     }
 246     if (MZ_Current() && MZ_Current()->load_seg) pTask->flags |= TDBF_WINOLDAP;
 247
 248     pTask->version       = pModule->expected_version;
 249     pTask->hModule       = pModule->self;
 250     pTask->hParent       = GetCurrentTask();
 251     pTask->magic         = TDB_MAGIC;
 252     pTask->nCmdShow      = cmdShow;
 253     pTask->teb           = teb;
 254     pTask->curdrive      = DRIVE_GetCurrentDrive() | 0x80;
 255     strcpy( pTask->curdir, "\\" );
 256     lstrcpynA( pTask->curdir + 1, DRIVE_GetDosCwd( DRIVE_GetCurrentDrive() ),
 257                  sizeof(pTask->curdir) - 1 );
 258
 259       /* Create the thunks block */
 260
 261     TASK_CreateThunks( hTask, (int)&pTask->thunks - (int)pTask, 7 );
 262
 263       /* Copy the module name */
 264
 265     GetModuleName16( pModule->self, name, sizeof(name) );
 266     strncpy( pTask->module_name, name, sizeof(pTask->module_name) );
 267
 268       /* Allocate a selector for the PDB */
 269
 270     pTask->hPDB = GLOBAL_CreateBlock( GMEM_FIXED, &pTask->pdb, sizeof(PDB16),
 271                                     pModule->self, FALSE, FALSE, FALSE );
 272
 273       /* Fill the PDB */
 274
 275     pTask->pdb.int20 = 0x20cd;
 276     pTask->pdb.dispatcher[0] = 0x9a;  /* ljmp */
 277     PUT_DWORD(&pTask->pdb.dispatcher[1], (DWORD)NE_GetEntryPoint(
 278            GetModuleHandle16("KERNEL"), 102 ));  /* KERNEL.102 is DOS3Call() */
 279     pTask->pdb.savedint22 = INT_GetPMHandler( 0x22 );
 280     pTask->pdb.savedint23 = INT_GetPMHandler( 0x23 );
 281     pTask->pdb.savedint24 = INT_GetPMHandler( 0x24 );
 282     pTask->pdb.fileHandlesPtr =
 283         PTR_SEG_OFF_TO_SEGPTR( GlobalHandleToSel16(pTask->hPDB),
 284                                (int)&((PDB16 *)0)->fileHandles );
 285     pTask->pdb.hFileHandles = 0;
 286     memset( pTask->pdb.fileHandles, 0xff, sizeof(pTask->pdb.fileHandles) );
 287     pTask->pdb.environment    = current_envdb.env_sel;
 288     pTask->pdb.nbFiles        = 20;
 289
 290     /* Fill the command line */
 291
 292     if (!cmdline)
 293     {
 294         cmdline = current_envdb.cmd_line;
 295         /* remove the first word (program name) */
 296         if (*cmdline == '"')
 297             if (!(cmdline = strchr( cmdline+1, '"' ))) cmdline = current_envdb.cmd_line;
 298         while (*cmdline && (*cmdline != ' ') && (*cmdline != '\t')) cmdline++;
 299         while ((*cmdline == ' ') || (*cmdline == '\t')) cmdline++;
 300         len = strlen(cmdline);
 301     }
 302     if (len >= sizeof(pTask->pdb.cmdLine)) len = sizeof(pTask->pdb.cmdLine)-1;
 303     pTask->pdb.cmdLine[0] = len;
 304     memcpy( pTask->pdb.cmdLine + 1, cmdline, len );
 305     /* pTask->pdb.cmdLine[len+1] = 0; */
 306
 307     TRACE("module='%s' cmdline='%.*s' task=%04x\n", name, len, cmdline, hTask );
 308
 309       /* Get the compatibility flags */
 310
 311     pTask->compat_flags = GetProfileIntA( "Compatibility", name, 0 );
 312
 313       /* Allocate a code segment alias for the TDB */
 314
 315     pTask->hCSAlias = GLOBAL_CreateBlock( GMEM_FIXED, (void *)pTask,
 316                                           sizeof(TDB), pTask->hPDB, TRUE,
 317                                           FALSE, FALSE );
 318
 319       /* Set the owner of the environment block */
 320
 321     FarSetOwner16( pTask->pdb.environment, pTask->hPDB );
 322
 323       /* Default DTA overwrites command line */
 324
 325     pTask->dta = PTR_SEG_OFF_TO_SEGPTR( pTask->hPDB,
 326                                 (int)&pTask->pdb.cmdLine - (int)&pTask->pdb );
 327
 328     /* Create scheduler event for 16-bit tasks */
 329
 330     if ( !(pTask->flags & TDBF_WIN32) )
 331     {
 332         pTask->hEvent = CreateEventA( NULL, TRUE, FALSE, NULL );
 333         pTask->hEvent = ConvertToGlobalHandle( pTask->hEvent );
 334     }
 335
 336     /* Enter task handle into thread and process */
 337
 338     teb->htask16 = hTask;
 339     if (!initial_task) initial_task = hTask;
 340
 341     /* Add the task to the linked list */
 342
 343     SYSLEVEL_EnterWin16Lock();
 344     TASK_LinkTask( hTask );
 345     SYSLEVEL_LeaveWin16Lock();
 346
 347     return TRUE;
 348 }
 349
 350 /***********************************************************************
 351  *           TASK_DeleteTask
 352  */
 353 static void TASK_DeleteTask( HTASK16 hTask )
 354 {
 355     TDB *pTask;
 356     HGLOBAL16 hPDB;
 357
 358     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 359     hPDB = pTask->hPDB;
 360
 361     pTask->magic = 0xdead; /* invalidate signature */
 362
 363     /* Free the selector aliases */
 364
 365     GLOBAL_FreeBlock( pTask->hCSAlias );
 366     GLOBAL_FreeBlock( pTask->hPDB );
 367
 368     /* Free the task module */
 369
 370     FreeModule16( pTask->hModule );
 371
 372     /* Free the task structure itself */
 373
 374     GlobalFree16( hTask );
 375
 376     /* Free all memory used by this task (including the 32-bit stack, */
 377     /* the environment block and the thunk segments). */
 378
 379     GlobalFreeAll16( hPDB );
 380 }
 381
 382 /***********************************************************************
 383  *           TASK_KillTask
 384  */
 385 void TASK_KillTask( HTASK16 hTask )
 386 {
 387     TDB *pTask;
 388
 389     /* Enter the Win16Lock to protect global data structures */
 390     SYSLEVEL_EnterWin16Lock();
 391
 392     if ( !hTask ) hTask = GetCurrentTask();
 393     pTask = (TDB *)GlobalLock16( hTask );
 394     if ( !pTask )
 395     {
 396         SYSLEVEL_LeaveWin16Lock();
 397         return;
 398     }
 399
 400     TRACE("Killing task %04x\n", hTask );
 401
 402     /* Perform USER cleanup */
 403
 404     TASK_CallTaskSignalProc( USIG16_TERMINATION, hTask );
 405     PROCESS_CallUserSignalProc( USIG_PROCESS_EXIT, 0 );
 406     PROCESS_CallUserSignalProc( USIG_THREAD_EXIT, 0 );
 407     PROCESS_CallUserSignalProc( USIG_PROCESS_DESTROY, 0 );
 408
 409     if (nTaskCount <= 1)
 410     {
 411         TRACE("this is the last task, exiting\n" );
 412         ExitKernel16();
 413     }
 414
 415     /* FIXME: Hack! Send a message to the initial task so that
 416      * the GetMessage wakes up and the initial task can check whether
 417      * it is the only remaining one and terminate itself ...
 418      * The initial task should probably install hooks or something
 419      * to get informed about task termination :-/
 420      */
 421     Callout.PostAppMessage16( initial_task, WM_NULL, 0, 0 );
 422
 423     /* Remove the task from the list to be sure we never switch back to it */
 424     TASK_UnlinkTask( hTask );
 425     if( nTaskCount )
 426     {
 427         TDB* p = (TDB *)GlobalLock16( hFirstTask );
 428         while( p )
 429         {
 430             if( p->hYieldTo == hTask ) p->hYieldTo = 0;
 431             p = (TDB *)GlobalLock16( p->hNext );
 432         }
 433     }
 434
 435     pTask->nEvents = 0;
 436
 437     if ( hLockedTask == hTask )
 438         hLockedTask = 0;
 439
 440     TASK_DeleteTask( hTask );
 441
 442     /* When deleting the current task ... */
 443     if ( hTask == hCurrentTask )
 444     {
 445         DWORD lockCount;
 446
 447         /* ... schedule another one ... */
 448         TASK_Reschedule();
 449
 450         /* ... and completely release the Win16Lock, just in case. */
 451         ReleaseThunkLock( &lockCount );
 452
 453         return;
 454     }
 455
 456     SYSLEVEL_LeaveWin16Lock();
 457 }
 458
 459 /***********************************************************************
 460  *           TASK_Reschedule
 461  *
 462  * This is where all the magic of task-switching happens!
 463  *
 464  * 16-bit Windows performs non-preemptive (cooperative) multitasking.
 465  * This means that each 16-bit task runs until it voluntarily yields
 466  * control, at which point the scheduler gets active and selects the
 467  * next task to run.
 468  *
 469  * In Wine, all processes, even 16-bit ones, are scheduled preemptively
 470  * by the standard scheduler of the underlying OS.  As many 16-bit apps
 471  * *rely* on the behaviour of the Windows scheduler, however, we have
 472  * to simulate that behaviour.
 473  *
 474  * This is achieved as follows: every 16-bit task is at time (except
 475  * during task creation and deletion) in one of two states: either it
 476  * is the one currently running, then the global variable hCurrentTask
 477  * contains its task handle, or it is not currently running, then it
 478  * is blocked on a special scheduler event, a global handle to which
 479  * is stored in the task struct.
 480  *
 481  * When the current task yields control, this routine gets called. Its
 482  * purpose is to determine the next task to be active, signal the
 483  * scheduler event of that task, and then put the current task to sleep
 484  * waiting for *its* scheduler event to get signalled again.
 485  *
 486  * This routine can get called in a few other special situations as well:
 487  *
 488  * - On creation of a 16-bit task, the Unix process executing the task
 489  *   calls TASK_Reschedule once it has completed its initialization.
 490  *   At this point, the task needs to be blocked until its scheduler
 491  *   event is signalled the first time (this will be done by the parent
 492  *   process to get the task up and running).
 493  *
 494  * - When the task currently running terminates itself, this routine gets
 495  *   called and has to schedule another task, *without* blocking the
 496  *   terminating task.
 497  *
 498  * - When a 32-bit thread posts an event for a 16-bit task, it might be
 499  *   the case that *no* 16-bit task is currently running.  In this case
 500  *   the task that has now an event pending is to be scheduled.
 501  *
 502  */
 503 void TASK_Reschedule(void)
 504 {
 505     TDB *pOldTask = NULL, *pNewTask = NULL;
 506     HTASK16 hOldTask = 0, hNewTask = 0;
 507     enum { MODE_YIELD, MODE_SLEEP, MODE_WAKEUP } mode;
 508     DWORD lockCount;
 509
 510     SYSLEVEL_EnterWin16Lock();
 511
 512     /* Check what we need to do */
 513     hOldTask = GetCurrentTask();
 514     pOldTask = (TDB *)GlobalLock16( hOldTask );
 515     TRACE( "entered with hCurrentTask %04x by hTask %04x (pid %ld)\n",
 516            hCurrentTask, hOldTask, (long) getpid() );
 517
 518     if ( pOldTask && THREAD_IsWin16( NtCurrentTeb() ) )
 519     {
 520         /* We are called by an active (non-deleted) 16-bit task */
 521
 522         /* If we don't even have a current task, or else the current
 523            task has yielded, we'll need to schedule a new task and
 524            (possibly) put the calling task to sleep.  Otherwise, we
 525            only block the caller. */
 526
 527         if ( !hCurrentTask || hCurrentTask == hOldTask )
 528             mode = MODE_YIELD;
 529         else
 530             mode = MODE_SLEEP;
 531     }
 532     else
 533     {
 534         /* We are called by a deleted 16-bit task or a 32-bit thread */
 535
 536         /* The only situation where we need to do something is if we
 537            now do not have a current task.  Then, we'll need to wake up
 538            some task that has events pending. */
 539
 540         if ( !hCurrentTask || hCurrentTask == hOldTask )
 541             mode = MODE_WAKEUP;
 542         else
 543         {
 544             /* nothing to do */
 545             SYSLEVEL_LeaveWin16Lock();
 546             return;
 547         }
 548     }
 549
 550     /* Find a task to yield to: check for DirectedYield() */
 551     if ( mode == MODE_YIELD && pOldTask && pOldTask->hYieldTo )
 552     {
 553         hNewTask = pOldTask->hYieldTo;
 554         pNewTask = (TDB *)GlobalLock16( hNewTask );
 555         if( !pNewTask || !pNewTask->nEvents) hNewTask = 0;
 556         pOldTask->hYieldTo = 0;
 557     }
 558
 559     /* Find a task to yield to: check for pending events */
 560     if ( (mode == MODE_YIELD || mode == MODE_WAKEUP) && !hNewTask )
 561     {
 562         hNewTask = hFirstTask;
 563         while (hNewTask)
 564         {
 565             pNewTask = (TDB *)GlobalLock16( hNewTask );
 566
 567             TRACE( "\ttask = %04x, events = %i\n", hNewTask, pNewTask->nEvents );
 568
 569             if (pNewTask->nEvents) break;
 570             hNewTask = pNewTask->hNext;
 571         }
 572         if (hLockedTask && (hNewTask != hLockedTask)) hNewTask = 0;
 573     }
 574
 575     /* If we are still the task with highest priority, just return ... */
 576     if ( mode == MODE_YIELD && hNewTask && hNewTask == hCurrentTask )
 577     {
 578         TRACE("returning to the current task (%04x)\n", hCurrentTask );
 579         SYSLEVEL_LeaveWin16Lock();
 580
 581         /* Allow Win32 threads to thunk down even while a Win16 task is
 582            in a tight PeekMessage() or Yield() loop ... */
 583         ReleaseThunkLock( &lockCount );
 584         RestoreThunkLock( lockCount );
 585         return;
 586     }
 587
 588     /* If no task to yield to found, suspend 16-bit scheduler ... */
 589     if ( mode == MODE_YIELD && !hNewTask )
 590     {
 591         TRACE("No currently active task\n");
 592         hCurrentTask = 0;
 593     }
 594
 595     /* If we found a task to wake up, do it ... */
 596     if ( (mode == MODE_YIELD || mode == MODE_WAKEUP) && hNewTask )
 597     {
 598         TRACE("Switching to task %04x (%.8s)\n",
 599                       hNewTask, pNewTask->module_name );
 600
 601         pNewTask->priority++;
 602         TASK_UnlinkTask( hNewTask );
 603         TASK_LinkTask( hNewTask );
 604         pNewTask->priority--;
 605
 606         hCurrentTask = hNewTask;
 607         SetEvent( pNewTask->hEvent );
 608
 609         /* This is set just in case some app reads it ... */
 610         pNewTask->ss_sp = pNewTask->teb->cur_stack;
 611     }
 612
 613     /* If we need to put the current task to sleep, do it ... */
 614     if ( (mode == MODE_YIELD || mode == MODE_SLEEP) && hOldTask != hCurrentTask )
 615     {
 616         ResetEvent( pOldTask->hEvent );
 617
 618         ReleaseThunkLock( &lockCount );
 619         SYSLEVEL_CheckNotLevel( 1 );
 620         WaitForSingleObject( pOldTask->hEvent, INFINITE );
 621         RestoreThunkLock( lockCount );
 622     }
 623
 624     SYSLEVEL_LeaveWin16Lock();
 625 }
 626
 627 /***********************************************************************
 628  *           InitTask  (KERNEL.91)
 629  *
 630  * Called by the application startup code.
 631  */
 632 void WINAPI InitTask16( CONTEXT86 *context )
 633 {
 634     TDB *pTask;
 635     INSTANCEDATA *pinstance;
 636     SEGPTR ptr;
 637
 638     EAX_reg(context) = 0;
 639     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
 640
 641     /* Note: we need to trust that BX/CX contain the stack/heap sizes,
 642        as some apps, notably Visual Basic apps, *modify* the heap/stack
 643        size of the instance data segment before calling InitTask() */
 644
 645     /* Initialize the INSTANCEDATA structure */
 646     pinstance = (INSTANCEDATA *)PTR_SEG_OFF_TO_LIN(CURRENT_DS, 0);
 647     pinstance->stackmin    = OFFSETOF( pTask->teb->cur_stack ) + sizeof( STACK16FRAME );
 648     pinstance->stackbottom = pinstance->stackmin; /* yup, that's right. Confused me too. */
 649     pinstance->stacktop    = ( pinstance->stackmin > BX_reg(context)?
 650                                pinstance->stackmin - BX_reg(context) : 0 ) + 150;
 651
 652     /* Initialize the local heap */
 653     if ( CX_reg(context) )
 654         LocalInit16( GlobalHandleToSel16(pTask->hInstance), 0, CX_reg(context) );
 655
 656     /* Initialize implicitly loaded DLLs */
 657     NE_InitializeDLLs( pTask->hModule );
 658     NE_DllProcessAttach( pTask->hModule );
 659
 660     /* Registers on return are:
 661      * ax     1 if OK, 0 on error
 662      * cx     stack limit in bytes
 663      * dx     cmdShow parameter
 664      * si     instance handle of the previous instance
 665      * di     instance handle of the new task
 666      * es:bx  pointer to command line inside PSP
 667      *
 668      * 0 (=%bp) is pushed on the stack
 669      */
 670     ptr = stack16_push( sizeof(WORD) );
 671     *(WORD *)PTR_SEG_TO_LIN(ptr) = 0;
 672     ESP_reg(context) -= 2;
 673
 674     EAX_reg(context) = 1;
 675
 676     if (!pTask->pdb.cmdLine[0]) EBX_reg(context) = 0x80;
 677     else
 678     {
 679         LPBYTE p = &pTask->pdb.cmdLine[1];
 680         while ((*p == ' ') || (*p == '\t')) p++;
 681         EBX_reg(context) = 0x80 + (p - pTask->pdb.cmdLine);
 682     }
 683     ECX_reg(context) = pinstance->stacktop;
 684     EDX_reg(context) = pTask->nCmdShow;
 685     ESI_reg(context) = (DWORD)pTask->hPrevInstance;
 686     EDI_reg(context) = (DWORD)pTask->hInstance;
 687     ES_reg (context) = (WORD)pTask->hPDB;
 688 }
 689
 690
 691 /***********************************************************************
 692  *           WaitEvent  (KERNEL.30)
 693  */
 694 BOOL16 WINAPI WaitEvent16( HTASK16 hTask )
 695 {
 696     TDB *pTask;
 697
 698     if (!hTask) hTask = GetCurrentTask();
 699     pTask = (TDB *)GlobalLock16( hTask );
 700
 701     if ( !THREAD_IsWin16( NtCurrentTeb() ) )
 702     {
 703         FIXME("called for Win32 thread (%04x)!\n", NtCurrentTeb()->teb_sel);
 704         return TRUE;
 705     }
 706
 707     if (pTask->nEvents > 0)
 708     {
 709         pTask->nEvents--;
 710         return FALSE;
 711     }
 712     TASK_Reschedule();
 713
 714     /* When we get back here, we have an event */
 715
 716     if (pTask->nEvents > 0) pTask->nEvents--;
 717     return TRUE;
 718 }
 719
 720
 721 /***********************************************************************
 722  *           PostEvent  (KERNEL.31)
 723  */
 724 void WINAPI PostEvent16( HTASK16 hTask )
 725 {
 726     TDB *pTask;
 727
 728     if (!hTask) hTask = GetCurrentTask();
 729     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 730
 731     if ( !THREAD_IsWin16( pTask->teb ) )
 732     {
 733         FIXME("called for Win32 thread (%04x)!\n", pTask->teb->teb_sel );
 734         return;
 735     }
 736
 737     pTask->nEvents++;
 738
 739     /* If we are a 32-bit task, we might need to wake up the 16-bit scheduler */
 740     if ( !THREAD_IsWin16( NtCurrentTeb() ) )
 741         TASK_Reschedule();
 742 }
 743
 744
 745 /***********************************************************************
 746  *           SetPriority  (KERNEL.32)
 747  */
 748 void WINAPI SetPriority16( HTASK16 hTask, INT16 delta )
 749 {
 750     TDB *pTask;
 751     INT16 newpriority;
 752
 753     if (!hTask) hTask = GetCurrentTask();
 754     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return;
 755     newpriority = pTask->priority + delta;
 756     if (newpriority < -32) newpriority = -32;
 757     else if (newpriority > 15) newpriority = 15;
 758
 759     pTask->priority = newpriority + 1;
 760     TASK_UnlinkTask( hTask );
 761     TASK_LinkTask( hTask );
 762     pTask->priority--;
 763 }
 764
 765
 766 /***********************************************************************
 767  *           LockCurrentTask  (KERNEL.33)
 768  */
 769 HTASK16 WINAPI LockCurrentTask16( BOOL16 bLock )
 770 {
 771     if (bLock) hLockedTask = GetCurrentTask();
 772     else hLockedTask = 0;
 773     return hLockedTask;
 774 }
 775
 776
 777 /***********************************************************************
 778  *           IsTaskLocked  (KERNEL.122)
 779  */
 780 HTASK16 WINAPI IsTaskLocked16(void)
 781 {
 782     return hLockedTask;
 783 }
 784
 785
 786 /***********************************************************************
 787  *           OldYield  (KERNEL.117)
 788  */
 789 void WINAPI OldYield16(void)
 790 {
 791     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
 792
 793     if ( !THREAD_IsWin16( NtCurrentTeb() ) )
 794     {
 795         FIXME("called for Win32 thread (%04x)!\n", NtCurrentTeb()->teb_sel);
 796         return;
 797     }
 798
 799     if (pCurTask) pCurTask->nEvents++;  /* Make sure we get back here */
 800     TASK_Reschedule();
 801     if (pCurTask) pCurTask->nEvents--;
 802 }
 803
 804 /***********************************************************************
 805  *           WIN32_OldYield16  (KERNEL.447)
 806  */
 807 void WINAPI WIN32_OldYield16(void)
 808 {
 809    DWORD count;
 810
 811    ReleaseThunkLock(&count);
 812    RestoreThunkLock(count);
 813 }
 814
 815 /***********************************************************************
 816  *           DirectedYield  (KERNEL.150)
 817  */
 818 void WINAPI DirectedYield16( HTASK16 hTask )
 819 {
 820     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
 821
 822     if ( !THREAD_IsWin16( NtCurrentTeb() ) )
 823     {
 824         FIXME("called for Win32 thread (%04x)!\n", NtCurrentTeb()->teb_sel);
 825         return;
 826     }
 827
 828     TRACE("%04x: DirectedYield(%04x)\n", pCurTask->hSelf, hTask );
 829
 830     pCurTask->hYieldTo = hTask;
 831     OldYield16();
 832
 833     TRACE("%04x: back from DirectedYield(%04x)\n", pCurTask->hSelf, hTask );
 834 }
 835
 836 /***********************************************************************
 837  *           Yield16  (KERNEL.29)
 838  */
 839 void WINAPI Yield16(void)
 840 {
 841     TDB *pCurTask = (TDB *)GlobalLock16( GetCurrentTask() );
 842
 843     if (pCurTask) pCurTask->hYieldTo = 0;
 844     if (pCurTask && pCurTask->hQueue) Callout.UserYield16();
 845     else OldYield16();
 846 }
 847
 848 /***********************************************************************
 849  *           KERNEL_490  (KERNEL.490)
 850  */
 851 HTASK16 WINAPI KERNEL_490( HTASK16 someTask )
 852 {
 853     if ( !someTask ) return 0;
 854
 855     FIXME("(%04x): stub\n", someTask );
 856     return 0;
 857 }
 858
 859 /***********************************************************************
 860  *           MakeProcInstance16  (KERNEL.51)
 861  */
 862 FARPROC16 WINAPI MakeProcInstance16( FARPROC16 func, HANDLE16 hInstance )
 863 {
 864     BYTE *thunk,*lfunc;
 865     SEGPTR thunkaddr;
 866     WORD hInstanceSelector;
 867
 868     hInstanceSelector = GlobalHandleToSel16(hInstance);
 869
 870     TRACE("(%08lx, %04x);\n", (DWORD)func, hInstance);
 871
 872     if (!HIWORD(func)) {
 873       /* Win95 actually protects via SEH, but this is better for debugging */
 874       ERR("Ouch ! Called with invalid func 0x%08lx !\n", (DWORD)func);
 875       return (FARPROC16)0;
 876     }
 877
 878     if (hInstance)
 879     {
 880         if ( (!(hInstance & 4)) ||
 881              ((hInstance != 0xffff) && IS_SELECTOR_FREE(hInstance|7)) )
 882         {
 883             ERR("Invalid hInstance (%04x) passed to MakeProcInstance !\n",
 884                 hInstance);
 885             return 0;
 886         }
 887     }
 888
 889     if ( (CURRENT_DS != hInstanceSelector)
 890       && (hInstance != 0)
 891       && (hInstance != 0xffff) )
 892     {
 893         /* calling MPI with a foreign DSEG is invalid ! */
 894         ERR("Problem with hInstance? Got %04x, using %04x instead\n",
 895                    hInstance,CURRENT_DS);
 896     }
 897
 898     /* Always use the DSEG that MPI was entered with.
 899      * We used to set hInstance to GetTaskDS16(), but this should be wrong
 900      * as CURRENT_DS provides the DSEG value we need.
 901      * ("calling" DS, *not* "task" DS !) */
 902     hInstanceSelector = CURRENT_DS;
 903     hInstance = GlobalHandle16(hInstanceSelector);
 904
 905     /* no thunking for DLLs */
 906     if (NE_GetPtr(FarGetOwner16(hInstance))->flags & NE_FFLAGS_LIBMODULE)
 907         return func;
 908
 909     thunkaddr = TASK_AllocThunk( GetCurrentTask() );
 910     if (!thunkaddr) return (FARPROC16)0;
 911     thunk = PTR_SEG_TO_LIN( thunkaddr );
 912     lfunc = PTR_SEG_TO_LIN( func );
 913
 914     TRACE("(%08lx,%04x): got thunk %08lx\n",
 915           (DWORD)func, hInstance, (DWORD)thunkaddr );
 916     if (((lfunc[0]==0x8c) && (lfunc[1]==0xd8)) || /* movw %ds, %ax */
 917         ((lfunc[0]==0x1e) && (lfunc[1]==0x58))    /* pushw %ds, popw %ax */
 918     ) {
 919         FIXME("This was the (in)famous \"thunk useless\" warning. We thought we have to overwrite with nop;nop;, but this isn't true.\n");
 920     }
 921
 922     *thunk++ = 0xb8;    /* movw instance, %ax */
 923     *thunk++ = (BYTE)(hInstanceSelector & 0xff);
 924     *thunk++ = (BYTE)(hInstanceSelector >> 8);
 925     *thunk++ = 0xea;    /* ljmp func */
 926     *(DWORD *)thunk = (DWORD)func;
 927     return (FARPROC16)thunkaddr;
 928     /* CX reg indicates if thunkaddr != NULL, implement if needed */
 929 }
 930
 931
 932 /***********************************************************************
 933  *           FreeProcInstance16  (KERNEL.52)
 934  */
 935 void WINAPI FreeProcInstance16( FARPROC16 func )
 936 {
 937     TRACE("(%08lx)\n", (DWORD)func );
 938     TASK_FreeThunk( GetCurrentTask(), (SEGPTR)func );
 939 }
 940
 941 /**********************************************************************
 942  *          TASK_GetCodeSegment
 943  *
 944  * Helper function for GetCodeHandle/GetCodeInfo: Retrieve the module
 945  * and logical segment number of a given code segment.
 946  *
 947  * 'proc' either *is* already a pair of module handle and segment number,
 948  * in which case there's nothing to do.  Otherwise, it is a pointer to
 949  * a function, and we need to retrieve the code segment.  If the pointer
 950  * happens to point to a thunk, we'll retrieve info about the code segment
 951  * where the function pointed to by the thunk resides, not the thunk itself.
 952  *
 953  * FIXME: if 'proc' is a SNOOP16 return stub, we should retrieve info about
 954  *        the function the snoop code will return to ...
 955  *
 956  */
 957 static BOOL TASK_GetCodeSegment( FARPROC16 proc, NE_MODULE **ppModule,
 958                                  SEGTABLEENTRY **ppSeg, int *pSegNr )
 959 {
 960     NE_MODULE *pModule = NULL;
 961     SEGTABLEENTRY *pSeg = NULL;
 962     int segNr;
 963
 964     /* Try pair of module handle / segment number */
 965     pModule = (NE_MODULE *) GlobalLock16( HIWORD( proc ) );
 966     if ( pModule && pModule->magic == IMAGE_OS2_SIGNATURE )
 967     {
 968         segNr = LOWORD( proc );
 969         if ( segNr && segNr <= pModule->seg_count )
 970             pSeg = NE_SEG_TABLE( pModule ) + segNr-1;
 971     }
 972
 973     /* Try thunk or function */
 974     else
 975     {
 976         BYTE *thunk = (BYTE *)PTR_SEG_TO_LIN( proc );
 977         WORD selector;
 978
 979         if ((thunk[0] == 0xb8) && (thunk[3] == 0xea))
 980             selector = thunk[6] + (thunk[7] << 8);
 981         else
 982             selector = HIWORD( proc );
 983
 984         pModule = NE_GetPtr( GlobalHandle16( selector ) );
 985         pSeg = pModule? NE_SEG_TABLE( pModule ) : NULL;
 986
 987         if ( pModule )
 988             for ( segNr = 1; segNr <= pModule->seg_count; segNr++, pSeg++ )
 989                 if ( GlobalHandleToSel16(pSeg->hSeg) == selector )
 990                     break;
 991
 992         if ( pModule && segNr > pModule->seg_count )
 993             pSeg = NULL;
 994     }
 995
 996     /* Abort if segment not found */
 997
 998     if ( !pModule || !pSeg )
 999         return FALSE;
1000
1001     /* Return segment data */
1002
1003     if ( ppModule ) *ppModule = pModule;
1004     if ( ppSeg    ) *ppSeg    = pSeg;
1005     if ( pSegNr   ) *pSegNr   = segNr;
1006
1007     return TRUE;
1008 }
1009
1010 /**********************************************************************
1011  *          GetCodeHandle    (KERNEL.93)
1012  */
1013 HANDLE16 WINAPI GetCodeHandle16( FARPROC16 proc )
1014 {
1015     SEGTABLEENTRY *pSeg;
1016
1017     if ( !TASK_GetCodeSegment( proc, NULL, &pSeg, NULL ) )
1018         return (HANDLE16)0;
1019
1020     return pSeg->hSeg;
1021 }
1022
1023 /**********************************************************************
1024  *          GetCodeInfo    (KERNEL.104)
1025  */
1026 BOOL16 WINAPI GetCodeInfo16( FARPROC16 proc, SEGINFO *segInfo )
1027 {
1028     NE_MODULE *pModule;
1029     SEGTABLEENTRY *pSeg;
1030     int segNr;
1031
1032     if ( !TASK_GetCodeSegment( proc, &pModule, &pSeg, &segNr ) )
1033         return FALSE;
1034
1035     /* Fill in segment information */
1036
1037     segInfo->offSegment = pSeg->filepos;
1038     segInfo->cbSegment  = pSeg->size;
1039     segInfo->flags      = pSeg->flags;
1040     segInfo->cbAlloc    = pSeg->minsize;
1041     segInfo->h          = pSeg->hSeg;
1042     segInfo->alignShift = pModule->alignment;
1043
1044     if ( segNr == pModule->dgroup )
1045         segInfo->cbAlloc += pModule->heap_size + pModule->stack_size;
1046
1047     /* Return module handle in %es */
1048
1049     CURRENT_STACK16->es = GlobalHandleToSel16( pModule->self );
1050
1051     return TRUE;
1052 }
1053
1054
1055 /**********************************************************************
1056  *          DefineHandleTable16    (KERNEL.94)
1057  */
1058 BOOL16 WINAPI DefineHandleTable16( WORD wOffset )
1059 {
1060     FIXME("(%04x): stub ?\n", wOffset);
1061     return TRUE;
1062 }
1063
1064
1065 /***********************************************************************
1066  *           SetTaskQueue  (KERNEL.34)
1067  */
1068 HQUEUE16 WINAPI SetTaskQueue16( HTASK16 hTask, HQUEUE16 hQueue )
1069 {
1070     HQUEUE16 hPrev;
1071     TDB *pTask;
1072
1073     if (!hTask) hTask = GetCurrentTask();
1074     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
1075
1076     hPrev = pTask->hQueue;
1077     pTask->hQueue = hQueue;
1078
1079     return hPrev;
1080 }
1081
1082
1083 /***********************************************************************
1084  *           GetTaskQueue  (KERNEL.35)
1085  */
1086 HQUEUE16 WINAPI GetTaskQueue16( HTASK16 hTask )
1087 {
1088     TDB *pTask;
1089
1090     if (!hTask) hTask = GetCurrentTask();
1091     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return 0;
1092     return pTask->hQueue;
1093 }
1094
1095 /***********************************************************************
1096  *           SetThreadQueue  (KERNEL.463)
1097  */
1098 HQUEUE16 WINAPI SetThreadQueue16( DWORD thread, HQUEUE16 hQueue )
1099 {
1100     TEB *teb = thread? THREAD_IdToTEB( thread ) : NtCurrentTeb();
1101     HQUEUE16 oldQueue = teb? teb->queue : 0;
1102
1103     if ( teb )
1104     {
1105         teb->queue = hQueue;
1106
1107         if ( GetTaskQueue16( teb->htask16 ) == oldQueue )
1108             SetTaskQueue16( teb->htask16, hQueue );
1109     }
1110
1111     return oldQueue;
1112 }
1113
1114 /***********************************************************************
1115  *           GetThreadQueue  (KERNEL.464)
1116  */
1117 HQUEUE16 WINAPI GetThreadQueue16( DWORD thread )
1118 {
1119     TEB *teb = NULL;
1120     if ( !thread )
1121         teb = NtCurrentTeb();
1122     else if ( HIWORD(thread) )
1123         teb = THREAD_IdToTEB( thread );
1124     else if ( IsTask16( (HTASK16)thread ) )
1125         teb = ((TDB *)GlobalLock16( (HANDLE16)thread ))->teb;
1126
1127     return (HQUEUE16)(teb? teb->queue : 0);
1128 }
1129
1130 /***********************************************************************
1131  *           SetFastQueue  (KERNEL.624)
1132  */
1133 VOID WINAPI SetFastQueue16( DWORD thread, HANDLE hQueue )
1134 {
1135     TEB *teb = NULL;
1136     if ( !thread )
1137         teb = NtCurrentTeb();
1138     else if ( HIWORD(thread) )
1139         teb = THREAD_IdToTEB( thread );
1140     else if ( IsTask16( (HTASK16)thread ) )
1141         teb = ((TDB *)GlobalLock16( (HANDLE16)thread ))->teb;
1142
1143     if ( teb ) teb->queue = (HQUEUE16) hQueue;
1144 }
1145
1146 /***********************************************************************
1147  *           GetFastQueue  (KERNEL.625)
1148  */
1149 HANDLE WINAPI GetFastQueue16( void )
1150 {
1151     TEB *teb = NtCurrentTeb();
1152     if (!teb) return 0;
1153
1154     if (!teb->queue)
1155         Callout.InitThreadInput16( 0, THREAD_IsWin16(teb)? 4 : 5 );
1156
1157     if (!teb->queue)
1158         FIXME("(): should initialize thread-local queue, expect failure!\n" );
1159
1160     return (HANDLE)teb->queue;
1161 }
1162
1163 /***********************************************************************
1164  *           SwitchStackTo   (KERNEL.108)
1165  */
1166 void WINAPI SwitchStackTo16( WORD seg, WORD ptr, WORD top )
1167 {
1168     TDB *pTask;
1169     STACK16FRAME *oldFrame, *newFrame;
1170     INSTANCEDATA *pData;
1171     UINT16 copySize;
1172
1173     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1174     if (!(pData = (INSTANCEDATA *)GlobalLock16( seg ))) return;
1175     TRACE("old=%04x:%04x new=%04x:%04x\n",
1176           SELECTOROF( pTask->teb->cur_stack ),
1177           OFFSETOF( pTask->teb->cur_stack ), seg, ptr );
1178
1179     /* Save the old stack */
1180
1181     oldFrame = THREAD_STACK16( pTask->teb );
1182     /* pop frame + args and push bp */
1183     pData->old_ss_sp   = pTask->teb->cur_stack + sizeof(STACK16FRAME)
1184                            + 2 * sizeof(WORD);
1185     *(WORD *)PTR_SEG_TO_LIN(pData->old_ss_sp) = oldFrame->bp;
1186     pData->stacktop    = top;
1187     pData->stackmin    = ptr;
1188     pData->stackbottom = ptr;
1189
1190     /* Switch to the new stack */
1191
1192     /* Note: we need to take the 3 arguments into account; otherwise,
1193      * the stack will underflow upon return from this function.
1194      */
1195     copySize = oldFrame->bp - OFFSETOF(pData->old_ss_sp);
1196     copySize += 3 * sizeof(WORD) + sizeof(STACK16FRAME);
1197     pTask->teb->cur_stack = PTR_SEG_OFF_TO_SEGPTR( seg, ptr - copySize );
1198     newFrame = THREAD_STACK16( pTask->teb );
1199
1200     /* Copy the stack frame and the local variables to the new stack */
1201
1202     memmove( newFrame, oldFrame, copySize );
1203     newFrame->bp = ptr;
1204     *(WORD *)PTR_SEG_OFF_TO_LIN( seg, ptr ) = 0;  /* clear previous bp */
1205 }
1206
1207
1208 /***********************************************************************
1209  *           SwitchStackBack   (KERNEL.109)
1210  */
1211 void WINAPI SwitchStackBack16( CONTEXT86 *context )
1212 {
1213     STACK16FRAME *oldFrame, *newFrame;
1214     INSTANCEDATA *pData;
1215
1216     if (!(pData = (INSTANCEDATA *)GlobalLock16(SELECTOROF(NtCurrentTeb()->cur_stack))))
1217         return;
1218     if (!pData->old_ss_sp)
1219     {
1220         WARN("No previous SwitchStackTo\n" );
1221         return;
1222     }
1223     TRACE("restoring stack %04x:%04x\n",
1224           SELECTOROF(pData->old_ss_sp), OFFSETOF(pData->old_ss_sp) );
1225
1226     oldFrame = CURRENT_STACK16;
1227
1228     /* Pop bp from the previous stack */
1229
1230     BP_reg(context) = *(WORD *)PTR_SEG_TO_LIN(pData->old_ss_sp);
1231     pData->old_ss_sp += sizeof(WORD);
1232
1233     /* Switch back to the old stack */
1234
1235     NtCurrentTeb()->cur_stack = pData->old_ss_sp - sizeof(STACK16FRAME);
1236     SS_reg(context)  = SELECTOROF(pData->old_ss_sp);
1237     ESP_reg(context) = OFFSETOF(pData->old_ss_sp) - sizeof(DWORD); /*ret addr*/
1238     pData->old_ss_sp = 0;
1239
1240     /* Build a stack frame for the return */
1241
1242     newFrame = CURRENT_STACK16;
1243     newFrame->frame32     = oldFrame->frame32;
1244     newFrame->module_cs   = oldFrame->module_cs;
1245     newFrame->callfrom_ip = oldFrame->callfrom_ip;
1246     newFrame->entry_ip    = oldFrame->entry_ip;
1247 }
1248
1249
1250 /***********************************************************************
1251  *           GetTaskQueueDS16  (KERNEL.118)
1252  */
1253 void WINAPI GetTaskQueueDS16(void)
1254 {
1255     CURRENT_STACK16->ds = GlobalHandleToSel16( GetTaskQueue16(0) );
1256 }
1257
1258
1259 /***********************************************************************
1260  *           GetTaskQueueES16  (KERNEL.119)
1261  */
1262 void WINAPI GetTaskQueueES16(void)
1263 {
1264     CURRENT_STACK16->es = GlobalHandleToSel16( GetTaskQueue16(0) );
1265 }
1266
1267
1268 /***********************************************************************
1269  *           GetCurrentTask   (KERNEL.36)
1270  */
1271 HTASK16 WINAPI GetCurrentTask(void)
1272 {
1273     return NtCurrentTeb()->htask16;
1274 }
1275
1276 DWORD WINAPI WIN16_GetCurrentTask(void)
1277 {
1278     /* This is the version used by relay code; the first task is */
1279     /* returned in the high word of the result */
1280     return MAKELONG( GetCurrentTask(), hFirstTask );
1281 }
1282
1283
1284 /***********************************************************************
1285  *           GetCurrentPDB   (KERNEL.37)
1286  *
1287  * UNDOC: returns PSP of KERNEL in high word
1288  */
1289 DWORD WINAPI GetCurrentPDB16(void)
1290 {
1291     TDB *pTask;
1292
1293     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1294     return MAKELONG(pTask->hPDB, 0); /* FIXME */
1295 }
1296
1297
1298 /***********************************************************************
1299  *           GetCurPID16   (KERNEL.157)
1300  */
1301 DWORD WINAPI GetCurPID16( DWORD unused )
1302 {
1303     return 0;
1304 }
1305
1306
1307 /***********************************************************************
1308  *           GetInstanceData   (KERNEL.54)
1309  */
1310 INT16 WINAPI GetInstanceData16( HINSTANCE16 instance, WORD buffer, INT16 len )
1311 {
1312     char *ptr = (char *)GlobalLock16( instance );
1313     if (!ptr || !len) return 0;
1314     if ((int)buffer + len >= 0x10000) len = 0x10000 - buffer;
1315     memcpy( (char *)GlobalLock16(CURRENT_DS) + buffer, ptr + buffer, len );
1316     return len;
1317 }
1318
1319
1320 /***********************************************************************
1321  *           GetExeVersion   (KERNEL.105)
1322  */
1323 WORD WINAPI GetExeVersion16(void)
1324 {
1325     TDB *pTask;
1326
1327     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1328     return pTask->version;
1329 }
1330
1331
1332 /***********************************************************************
1333  *           SetErrorMode16   (KERNEL.107)
1334  */
1335 UINT16 WINAPI SetErrorMode16( UINT16 mode )
1336 {
1337     TDB *pTask;
1338     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1339     pTask->error_mode = mode;
1340     return SetErrorMode( mode );
1341 }
1342
1343
1344 /***********************************************************************
1345  *           GetDOSEnvironment   (KERNEL.131)
1346  */
1347 SEGPTR WINAPI GetDOSEnvironment16(void)
1348 {
1349     TDB *pTask;
1350
1351     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1352     return PTR_SEG_OFF_TO_SEGPTR( pTask->pdb.environment, 0 );
1353 }
1354
1355
1356 /***********************************************************************
1357  *           GetNumTasks   (KERNEL.152)
1358  */
1359 UINT16 WINAPI GetNumTasks16(void)
1360 {
1361     return nTaskCount;
1362 }
1363
1364
1365 /***********************************************************************
1366  *           GetTaskDS   (KERNEL.155)
1367  *
1368  * Note: this function apparently returns a DWORD with LOWORD == HIWORD.
1369  * I don't think we need to bother with this.
1370  */
1371 HINSTANCE16 WINAPI GetTaskDS16(void)
1372 {
1373     TDB *pTask;
1374
1375     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1376     return GlobalHandleToSel16(pTask->hInstance);
1377 }
1378
1379 /***********************************************************************
1380  *           GetDummyModuleHandleDS   (KERNEL.602)
1381  */
1382 WORD WINAPI GetDummyModuleHandleDS16(void)
1383 {
1384     TDB *pTask;
1385     WORD selector;
1386
1387     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1388     if (!(pTask->flags & TDBF_WIN32)) return 0;
1389     selector = GlobalHandleToSel16( pTask->hModule );
1390     CURRENT_DS = selector;
1391     return selector;
1392 }
1393
1394 /***********************************************************************
1395  *           IsTask   (KERNEL.320)
1396  */
1397 BOOL16 WINAPI IsTask16( HTASK16 hTask )
1398 {
1399     TDB *pTask;
1400
1401     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return FALSE;
1402     if (GlobalSize16( hTask ) < sizeof(TDB)) return FALSE;
1403     return (pTask->magic == TDB_MAGIC);
1404 }
1405
1406
1407 /***********************************************************************
1408  *           IsWinOldApTask16   (KERNEL.158)
1409  */
1410 BOOL16 WINAPI IsWinOldApTask16( HTASK16 hTask )
1411 {
1412     /* should return bit 0 of byte 0x48 in PSP */
1413     return FALSE;
1414 }
1415
1416 /***********************************************************************
1417  *           SetTaskSignalProc   (KERNEL.38)
1418  */
1419 FARPROC16 WINAPI SetTaskSignalProc( HTASK16 hTask, FARPROC16 proc )
1420 {
1421     TDB *pTask;
1422     FARPROC16 oldProc;
1423
1424     if (!hTask) hTask = GetCurrentTask();
1425     if (!(pTask = (TDB *)GlobalLock16( hTask ))) return NULL;
1426     oldProc = pTask->userhandler;
1427     pTask->userhandler = proc;
1428     return oldProc;
1429 }
1430
1431 /***********************************************************************
1432  *           TASK_CallTaskSignalProc
1433  */
1434 /* ### start build ### */
1435 extern WORD CALLBACK TASK_CallTo16_word_wwwww(FARPROC16,WORD,WORD,WORD,WORD,WORD);
1436 /* ### stop build ### */
1437 void TASK_CallTaskSignalProc( UINT16 uCode, HANDLE16 hTaskOrModule )
1438 {
1439     TDB *pTask = (TDB *)GlobalLock16( GetCurrentTask() );
1440     if ( !pTask || !pTask->userhandler ) return;
1441
1442     TASK_CallTo16_word_wwwww( pTask->userhandler,
1443                               hTaskOrModule, uCode, 0,
1444                               pTask->hInstance, pTask->hQueue );
1445 }
1446
1447 /***********************************************************************
1448  *           SetSigHandler   (KERNEL.140)
1449  */
1450 WORD WINAPI SetSigHandler16( FARPROC16 newhandler, FARPROC16* oldhandler,
1451                            UINT16 *oldmode, UINT16 newmode, UINT16 flag )
1452 {
1453     FIXME("(%p,%p,%p,%d,%d), unimplemented.\n",
1454           newhandler,oldhandler,oldmode,newmode,flag );
1455
1456     if (flag != 1) return 0;
1457     if (!newmode) newhandler = NULL;  /* Default handler */
1458     if (newmode != 4)
1459     {
1460         TDB *pTask;
1461
1462         if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return 0;
1463         if (oldmode) *oldmode = pTask->signal_flags;
1464         pTask->signal_flags = newmode;
1465         if (oldhandler) *oldhandler = pTask->sighandler;
1466         pTask->sighandler = newhandler;
1467     }
1468     return 0;
1469 }
1470
1471
1472 /***********************************************************************
1473  *           GlobalNotify   (KERNEL.154)
1474  *
1475  * Note that GlobalNotify does _not_ return the old NotifyProc
1476  * -- contrary to LocalNotify !!
1477  */
1478 VOID WINAPI GlobalNotify16( FARPROC16 proc )
1479 {
1480     TDB *pTask;
1481
1482     if (!(pTask = (TDB *)GlobalLock16( GetCurrentTask() ))) return;
1483     pTask->discardhandler = proc;
1484 }
1485
1486
1487 /***********************************************************************
1488  *           GetExePtr   (KERNEL.133)
1489  */
1490 static inline HMODULE16 GetExePtrHelper( HANDLE16 handle, HTASK16 *hTask )
1491 {
1492     char *ptr;
1493     HANDLE16 owner;
1494
1495       /* Check for module handle */
1496
1497     if (!(ptr = GlobalLock16( handle ))) return 0;
1498     if (((NE_MODULE *)ptr)->magic == IMAGE_OS2_SIGNATURE) return handle;
1499
1500       /* Search for this handle inside all tasks */
1501
1502     *hTask = hFirstTask;
1503     while (*hTask)
1504     {
1505         TDB *pTask = (TDB *)GlobalLock16( *hTask );
1506         if ((*hTask == handle) ||
1507             (pTask->hInstance == handle) ||
1508             (pTask->hQueue == handle) ||
1509             (pTask->hPDB == handle)) return pTask->hModule;
1510         *hTask = pTask->hNext;
1511     }
1512
1513       /* Check the owner for module handle */
1514
1515     owner = FarGetOwner16( handle );
1516     if (!(ptr = GlobalLock16( owner ))) return 0;
1517     if (((NE_MODULE *)ptr)->magic == IMAGE_OS2_SIGNATURE) return owner;
1518
1519       /* Search for the owner inside all tasks */
1520
1521     *hTask = hFirstTask;
1522     while (*hTask)
1523     {
1524         TDB *pTask = (TDB *)GlobalLock16( *hTask );
1525         if ((*hTask == owner) ||
1526             (pTask->hInstance == owner) ||
1527             (pTask->hQueue == owner) ||
1528             (pTask->hPDB == owner)) return pTask->hModule;
1529         *hTask = pTask->hNext;
1530     }
1531
1532     return 0;
1533 }
1534
1535 HMODULE16 WINAPI WIN16_GetExePtr( HANDLE16 handle )
1536 {
1537     HTASK16 hTask = 0;
1538     HMODULE16 hModule = GetExePtrHelper( handle, &hTask );
1539     STACK16FRAME *frame = CURRENT_STACK16;
1540     frame->ecx = hModule;
1541     if (hTask) frame->es = hTask;
1542     return hModule;
1543 }
1544
1545 HMODULE16 WINAPI GetExePtr( HANDLE16 handle )
1546 {
1547     HTASK16 hTask = 0;
1548     return GetExePtrHelper( handle, &hTask );
1549 }
1550
1551
1552 /***********************************************************************
1553  *           TaskFirst   (TOOLHELP.63)
1554  */
1555 BOOL16 WINAPI TaskFirst16( TASKENTRY *lpte )
1556 {
1557     lpte->hNext = hFirstTask;
1558     return TaskNext16( lpte );
1559 }
1560
1561
1562 /***********************************************************************
1563  *           TaskNext   (TOOLHELP.64)
1564  */
1565 BOOL16 WINAPI TaskNext16( TASKENTRY *lpte )
1566 {
1567     TDB *pTask;
1568     INSTANCEDATA *pInstData;
1569
1570     TRACE_(toolhelp)("(%p): task=%04x\n", lpte, lpte->hNext );
1571     if (!lpte->hNext) return FALSE;
1572     pTask = (TDB *)GlobalLock16( lpte->hNext );
1573     if (!pTask || pTask->magic != TDB_MAGIC) return FALSE;
1574     pInstData = (INSTANCEDATA *)PTR_SEG_OFF_TO_LIN( GlobalHandleToSel16(pTask->hInstance), 0 );
1575     lpte->hTask         = lpte->hNext;
1576     lpte->hTaskParent   = pTask->hParent;
1577     lpte->hInst         = pTask->hInstance;
1578     lpte->hModule       = pTask->hModule;
1579     lpte->wSS           = SELECTOROF( pTask->teb->cur_stack );
1580     lpte->wSP           = OFFSETOF( pTask->teb->cur_stack );
1581     lpte->wStackTop     = pInstData->stacktop;
1582     lpte->wStackMinimum = pInstData->stackmin;
1583     lpte->wStackBottom  = pInstData->stackbottom;
1584     lpte->wcEvents      = pTask->nEvents;
1585     lpte->hQueue        = pTask->hQueue;
1586     lstrcpynA( lpte->szModule, pTask->module_name, sizeof(lpte->szModule) );
1587     lpte->wPSPOffset    = 0x100;  /*??*/
1588     lpte->hNext         = pTask->hNext;
1589     return TRUE;
1590 }
1591
1592
1593 /***********************************************************************
1594  *           TaskFindHandle   (TOOLHELP.65)
1595  */
1596 BOOL16 WINAPI TaskFindHandle16( TASKENTRY *lpte, HTASK16 hTask )
1597 {
1598     lpte->hNext = hTask;
1599     return TaskNext16( lpte );
1600 }
1601
1602
1603 /***********************************************************************
1604  *           GetAppCompatFlags16   (KERNEL.354)
1605  */
1606 DWORD WINAPI GetAppCompatFlags16( HTASK16 hTask )
1607 {
1608     return GetAppCompatFlags( hTask );
1609 }
1610
1611
1612 /***********************************************************************
1613  *           GetAppCompatFlags   (USER32.206)
1614  */
1615 DWORD WINAPI GetAppCompatFlags( HTASK hTask )
1616 {
1617     TDB *pTask;
1618
1619     if (!hTask) hTask = GetCurrentTask();
1620     if (!(pTask=(TDB *)GlobalLock16( (HTASK16)hTask ))) return 0;
1621     if (GlobalSize16(hTask) < sizeof(TDB)) return 0;
1622     return pTask->compat_flags;
1623 }